Ventral hernias are abdominal wall defects that generally occur following a breakdown in the closure of a previous abdominal open surgical midline incision. 350,000-500,000 ventral hernias are repaired annually in the United States. Ventral hernias may be greater than 10 cm wide and 40 cm or more in length and extend below the xiphoid process of the sternum inferiorly to the pubic symphysis; they may be repaired via conventional “open” methods requiring a large incision, or laparoscopic procedures requiring small abdominal incisions.
Ventral hernias may arise after a patient undergoes abdominal surgery. For example, upon completion of an open abdominal surgical procedure, closure of the full thickness abdominal wall is performed. Interrupted sutures are placed through the anterior rectus sheath, the rectus muscle, and the posterior rectus sheath. Suture repair has a long-term failure rate of 41%-52%, leading to ventral hernia formation. Poor tissue strength coupled with significant tension in the suture lines leads to failure of the abdominal closure requiring hernia repair. In conventional laparoscopic repair, multiple trocar ports are inserted to place a large patch of prosthetic mesh to cover the defect. This approach causes far less postoperative pain as compared to open methods because a large abdominal incision is avoided. However, the abdominal defect is generally not closed; rather, the large prosthetic patch is tacked onto the inner surface of the abdominal wall to cover the defect. Placement of a large piece of artificial material results in a high rate of postoperative complications, including seroma formation. The fluid loculation of the seroma then increases the potential for infection of the laparoscopically placed mesh, necessitating its removal plus antibiotic therapy. Bowel adhesions are also a potential complication due to the implantation of a large foreign body patch.
It is desirable to close the abdominal defect using a laparoscopic technique, either partially or completely, to significantly decrease the size of the prosthetic mesh patch needed to repair the ventral hernia or eliminate the use of a mesh patch entirely at the discretion of the surgeon. U.S. Pat. No. 9,055,940 describes a system and technique that uses capture devices that puncture through the abdominal wall on both sides of the hernia defect and grasp the ends of a suture delivered into the abdominal cavity. One end of the suture is pulled out of the body, and a trapping device is tunneled subcutaneously from the first end of the suture to grasp and deliver the opposite end of the suture to the first puncture site. The suture may be tied at the first puncture site, and the knot inserted through the skin down to the level of the anterior rectus sheath, where it may be tensioned to close the hernia defect.
The technique illustrated in U.S. Pat. No. 9,055,940 is repeated for each interrupted suture placed during ventral hernia closure. If a relatively close spacing of 2 cm is used between sutures to increase the strength of the repair, and a 30 cm long hernia defect is being closed, 14 interrupted sutures will be required. With wide defects, the sutures must be tensioned incrementally and sequentially to gradually reappose the edges, otherwise, the suture may tear through the abdominal wall tissue. A slip knot composed of two half-hitches is used to allow sequential tensioning of an individual suture. Continuous tension must be maintained on all sutures during the cinching and closure process. This may be performed by applying a surgical clamp immediately proximal to each slip knot after each sequential tensioning step. However, this leads to an excessive number of surgical clamps on the operating field.
The aforementioned hernia defect closure technique is overly tedious. Placement of each interrupted suture involves the following steps: (1) Insert suture loop into the abdominal cavity; (2) Insert suture capture device through abdominal wall and capture one end of suture; (3) Pull captured suture end out of the patient; (3) Insert suture capture device through opposite side of abdominal wall and capture opposite end of suture; (4) Insert trapping device through first puncture site and tunnel to engage the suture capture device on opposite side of abdominal wall; (5) Remove suture capture device to pull the opposite end of the suture out of the patient; (6) Pull the trapping device out of the patient so both ends of the suture loop exit one abdominal puncture site; (7) Tie two half-hitches in the suture to form a slip knot; (8) Push slip knot down to the anterior rectus sheath using a knot pusher; (9) Clamp the suture near the knot to maintain tension in the suture loop; (10) Serially tension all placed suture loops to bring the edges of the hernia defect together; (11) Tie multiple square knots and use the knot pusher to push each knot down to the level of the anterior rectus sheath to fixate each interrupted suture loop; (12) Cut excess suture from each knot. Hence, at least twelve surgical manipulation steps must be performed for each of the ten or more sutures placed in the patient.
The anchor device of Surti (U.S. Pat. No. 9,339,265) discloses an anchor delivery tool wherein the tissue anchor lies within the bore of a needle. As the outer diameter of the needle is larger than the diameter of the anchor, there exists potential for an anchor under continuous tension to dilate the relatively large tract in the muscle formed by needle insertion, leading to pullout of the anchor through the dilated tract. This scenario may be observed particularly in the weakened or attenuated tissue encountered in ventral hernia patients.
A laparoscopic technique and instrumentation is desired to place multiple interrupted fastening loops on each side of a hernia defect, maintain tension in each loop, and allow serial cinching of each loop to reappose the edges of the defect while preventing the sutures from incising, pulling out, or tearing through the muscle tissue.